It may be not perfect for people preferring more "open" sound - well, that's only big clay ocarina, so the sound is a bit muffed by design.
Again, the labium is on the bottom - so again, we have lower volume and
less high frequencies survived.
Effect is really distinct - like more standard., "concert" transverse contrabass ocarina treated by lowpass filter.
I like it very much, it's perfect for meditation, for quiet play without stressing Your cochlear hair cells ;) and for studio work as well.
Nevertheless, is quite able in dynamic range department so I can imagine entire consort of these clams playing "live".
Well, I think I'm a bit addicted - I have decided to buy (in time) entire range of these Thomann clams - with recorders I can not afford that (beside plastic ones) :)
These "6+1 Holes" are sufficient mostly for everything, when You consider cross-fingerings and half-holing.
My recorder trained brain prefers that way (10 or 12 holes are overkill for me, just like with Sopilka flute from Ukraine). Interestingly there is Chinese rim-blown clay instrument, Xiao which has 8 or 10 holes, whan You train on Thomann's 7H Shell moving to 8-hole XIao is just a breeze.